It was well known that the ACA projections had something like 70-90% (I can't remember what the exact number was, but it's between those) of the newly insured being covered under Medicaid expansion. So basically, most of what the ACA is was a massive entitlement program expansion, which of course is enormously expensive. They fiddled with the numbers so the CBO would put its stamp of approval on it. That in itself is something to bitch about from a cost and big government perspective. The other part of it dealt with an abundance of mandates (even though RJ apparently thinks that mandate only means individual mandate) that are also objectionable from the small government perspective.
I don't know why you seem to think that "well known" equates to correct policy. I mean, if I have a policy that gives a new car to every teenager that gets his license, and the amount of teenagers with new cars goes up as a result, then that is an expected result. It doesn't mean it's good policy.